A New Criterion for Decision-Making in Mesh Simplification of 3D-Scanned Objects Used in Discrete-Element Modelling

Abstract

This paper describes mesh simplification of 3D-scanned objects, as used in discrete-element modelling (DEM). The mesh simplification algorithm parameter (R_p) is conventionally determined by trial-and-error based on the users’ judgment. We proposed a new criterion to quantify a balance of shape approximation accuracy and a quantity of meshes. A satisfactory R_p value was uniquely determined through minimization of the criterion. The proposed method was applied to mesh simplification in 3D-scanned waste electrical and electronic equipment, and successfully determined a satisfactory R_p value. To evaluate the determined R_p value, we performed a series of angle-of-repose DEM simulations using particles with different R_p values. The simulated repose angle converged to a constant value when the R_p was greater than a specific value. Its precise shape approximation reproduced the rotational resistance due to interparticle moment transmission that occurred upon contact of nonspherical particles. The R_p value was sufficient to obtain a constant value of repose angle, which indicated that the proposed method is valid for decision-making with respect to the selection of the R_p value used.